Brainwave research into epilepsy is suggesting that people with this condition may be quite profoundly affected even when they're not obviously having a seizure.

The brainwaves we're talking about are the electroencephalogram - the EEG - which measures electrical activity from multiple points on the scalp.

Neurologists can diagnose the condition from brain wave patterns which occur between fits and were thought to be harmless.

But by combining imaging of the brain in action with EEGs, researchers are finding that these brain wave patterns between seizure can be a sign of profound and wide ranging disturbances deep with the brain.

The unanswered question, especially in children is what the behavioural effects of this abnormal brain activity might be? The risk is that things like seeing and listening might be below par and if they are new treatments may be needed to control the situation. And with between 2 and 5 per cent of the population suffering a fit at some time in their lives, this isn't a rare problem.